This invention relates to a motor vehicle reciprocating linear sweeping wiping mechanism.
The invention aims to allow the wiping of a windshield or a rear window of a motor vehicle. According to the broadest conception in the domain of automobile construction, each wiper presents a reciprocating wiping of the window to be wiped in a reciprocating rotational movement around an axis notably fixed relative to the frame structure of the window. Such wiping, whether it is carried out by means of one wiper or by two parallel or opposing sweeping wipers, leaves relatively important parts of the window unwiped.
In order to remedy these inconveniences, complex mechanisms aiming to displace the articulation axis of each wiper arm in order to increase the surface effectively wiped have already been proposed: According to another conception, which is, for example, described and represented in documents DE-A-4.234.202 or FR-A-2.658.460, it has been proposed to carry out linear sweeping wiping of the window to be wiped by means of wiper mechanism comprising a guide and drive carriage which is mounted sliding relative to the vehicle body on at least one guide rail, or the equivalent, which extends the length of the window to be wiped, the length of the lower or upper edge of the window, or simultaneously the length of the two parallel edges of the window. The carriage bears a close end of an arm or of a wiper blade, the far end of which bears a window wiping scraper.
According to another conception, the wiper mechanism also comprises driving means of the carriage including, for example, a flexible driving element in a closed loop held between two pulleys and which is linked to the carriage, and a driving motor that transmits a running movement to the flexible guiding element. Thanks to such a conception, the wiper blade born by the wiper arm, or directly by the carriage, can carry out a quasi-complete wiping of the window to be wiped the contour of which is generally rectangular.
According to another conception of a reciprocating linear sweeping wiping mechanism described and represented in the document FR-A-2.027.739, this one comprising a guide and drive carriage which is slidably mounted on a least one rigid guide rail and which bears at least one wiper blade, the mechanism being the type that includes driving means of the carriage comprising an electric motor that drives in rotation an elongated element forming an endless screw that extends the length of the guide rail and which crosses a complementary nut born by the carriage.
In all known conceptions, the guide and drive carriage is mounted slidably on the length of at least one rigid guide rail that is produced in the form of a extruded profile. The guiding of the carriage on the rail in the form of a extruded profile is preferably carried out on the inside of the extruded profile, in order to guide the carriage in a precise manner while applying sufficient wiping effort on the wiping scraper and in a manner to carry out the guiding in an internal zone protected from pollution and dirt.
With this goal, the document GB-A-887.114 describes a reciprocating linear sweeping wiping mechanism comprising a guide and drive carriage bearing at least one wiping element, notably an arm or a wiper blade, and which is mounted slidingly on the inside of a rigid longitudinal guide rail produced in the form of a hollow extruded profile which, in a cross-section, comprises two opposing lateral slides in the form of a transversally open C relative to each other and each of which receives at least one complementary stabilization element born by a frame plate of the carriage lodged at least partially inside of the guide rail and which extends in a longitudinally horizontal plane parallel to the wiping plane, and of the type in which the frame plate bears means for longitudinal guiding that cooperate with the complementary means of the extruded profile in order to determine the transversal position of hte frame plate relative to the extruded profile.
According to the proposed conception in this document, the stabilization elements are casters mounted in rotation on the frame plate, around the horizontal axes, and the guiding means are equally made up of a set of casters, born in rotation by the frame plate around the vertical axes, which roll in the complementary gutters of the extruded profile.
It results in a complex conception of the extruded profile, a large number of components mounted in rotation and are thus susceptible to be used in making harmful sets appear as good guiding of the carriage, or which can be blocked by augmenting the general rubbing drag of the carriage relative to the guide rail.
In order to remedy these inconveniences, this invention proposes a mechanism of the type described and represented in document GB-A-887.114, characterized by the transversal positioning means of the frame plate relative to the extruded profile comprising a rigid rib with a transversal orientation born by the extruded profile, or by the frame plate, which is received via longitudinal sliding in a complementary longitudinal groove vertically open borne by the frame plate, or the respective extruded profile, and by each stabilization element being a stabilization pad which is received via longitudinal sliding on the inside of the corresponding C-shaped slide.
According to other characteristics of the invention:
the guide groove belongs to the frame plate of the carriage and is attached under a lower face of the frame plate in order to receive by sliding a rib formed in relief towards the top on an internal face of the extruded profile;
the groove belongs to a molded element, in a plastic material, brought back onto the frame plate, in the form of an element molded onto the plate;
each stabilization pad is received without play, according to a vertical direction, in the corresponding C-shaped slide;
each pad is elastically deformable in order to allow limited swing of the frame plate around a longitudinal horizontal axis;
the peripheral external surface of each stabilization pad that cooperates with the horizontal internal parallel and opposing faces of the corresponding slide in the shape of a C comprising a coating with a weak friction coefficient;
each stabilization pad is in the general shape of a flattened ring that is mounted on a rod of the frame plate that extends transversally to the inside of the corresponding C-shaped slide;
one of the internal horizontal parallel and opposing faces of the C-shaped slide is made up of the coplanar free edges of at least one longitudinal rib of the extruded profile;
the frame plate of the carriage bears at least two stabilization pads attached in a triangle among which two of the pads are received by sliding on one of the slides, while the third stabilization pad is received by sliding in another of the two C-shaped slides;
the guide rib is received without play according to the transversal direction to the inside of the complementary guide groove;
the frame plate is produced in serrated, folded and/or stamped, extruded, cut, punched sheet metal or molded with aluminum alloy or with plastic allowing one to obtain pads and slides cast in one piece to facilitate recycling;
the frame plate includes means for its joining with a flexible drive element of the carriage;
the extruded profile is produced in one piece, by extrusion or by molding;
the extruded profile comprises a continuous horizontal lower wing from which the C-shaped stabilization slides extend, and by the upper extruded profile face comprising at least one longitudinal slit for the passage, towards the exterior of the rail, of a pad that links the frame plate to the wiping element.